1. Field of the Invention
The present invention relates to eyeglass devices and, more particularly, but not by way of limitation, to eyeglass devices with auxiliary lenses or frames.
2. Description of the Related Art
Eyeglass devices typically include a primary frame for supporting two lenses that, depending upon the needs of a wearer, function to correct vision, provide eye protection, or shade the eyes. Due to these varying needs, some frames permit the interchanging of lenses or the attachment of auxiliary frames to the primary frames to provide the wearer flexibility.
One such eyeglass device is disclosed in U.S. Pat. No. 4,357,080, which issued on Nov. 2, 1982, to Solomon. Solomon includes an eyeglass frame having two latches. Hooks are positioned about the frame's periphery to secure the lenses to the frame. Each latch has a pivotable arm that, in a first horizontal position, secures a lens against the hooks and, in a second vertical position, permits removal of the lens from the hooks. To remove a lens, a wearer's finger pivots the latch arm upwards releasing the lens. Once the lens is removed from the hooks, another lens is slid underneath the hooks. Pivoting the arm downward secures the lens to the frame.
Another eyeglass device is disclosed in U.S. Pat. No. 5,416,537, which issued on May 16, 1995, to Sadler. The Sadler device includes a primary spectacle device and a separate one-piece lens. The primary spectacle device includes a bridge, two eyepieces, two temple members, and two primary lenses. Each eyepiece supports a single lens and is integrally formed with an opposing end of the bridge. The frame temple members permanently and pivotally connect to respective eyepieces. Each eyepiece also has a magnetic member connected to its face corresponding to the temporal region of the wearer. The one-piece lens has two magnetic members affixed to its backside. The lens's magnetic members connect with the primary magnetic members for facilitating the lens's attachment to and removal from the primary spectacle device.
A further eyeglass device is disclosed in U.S. Pat. No. 5,568,207, which issued on Oct. 22, 1996, to Chao. The Chao device includes a primary spectacle device and an auxiliary spectacle device. The primary spectacle device includes a bridge, two eyepieces, two temple members, two primary lenses, and two protrusions. Each eyepiece supports a single lens and is integrally formed with an opposing end of the bridge. The frame temple members permanently and pivotally connect to respective eyepieces. The protrusions have respective magnetic members and connect at the periphery of respective eyepieces. Each protrusion is located proximate to the connection of the respective eyepiece and temple member.
The auxiliary spectacle device includes a bridge, two eyepieces, and two arms. Each eyepiece supports a single lens and is integrally formed with an opposing end of the bridge. The arms are integrally formed with respective eyepieces and extend rearwardly from their respective eyepieces' periphery. Each arm has a magnetic member for engagement with respective magnetic members of the primary spectacle device. The magnetic members of both devices facilitate the auxiliary spectacle device's attachment to and removal from the primary spectacle device.
Although the Solomon frame design permits the interchanging of lenses, it suffers several disadvantages. A wearer requiring prescription lenses to correct vision defects cannot substitute non-prescription lenses if, for example, safety lenses are required because a substantial impairment of vision will occur. In addition, the latch arm is sometimes difficult to operate. The wearer's finger engages the relatively smooth, elongated latch arm to raise it. If moisture is present on the wearer's finger or the arm, the finger may slide off the arm's smooth surface, thereby failing to lift it.
Although the Sadler and Chao devices use magnets to attach a respective auxiliary lens or frame to a primary frame, both designs fail to properly secure the auxiliary piece. If the wearer should pivot his head rapidly downward, the auxiliary piece disengages from the primary frame. This accidental disengagement may result in damage to or loss of the auxiliary lens or frame.
Accordingly, an eyeglass device permitting a prescription lens wearer to wear non-prescription lenses and having an easily grasped latch arm, or an eyeglass device that enhances the securing of an auxiliary piece to a primary frame will improve over conventional eyeglasses.